Thermosetting resin compositions, such as an epoxy resin containing an inorganic filler, are widely used in semiconductor packages as a sealant for protecting a semiconductor element (chip) from the environment. The sealant seals multiple members with different coefficients of linear expansion, such as a chip, Cu, PPS (polyphenylene sulfide), and an insulating substrate. An inorganic filler added to the thermosetting resin decreases the coefficient of thermal expansion of the thermosetting resin, suppresses the warping of a cured resin product, and prevents interface peeling, cracks, and the like in a semiconductor package, from occurring.